Human Rights lawyer George Newhouse told SBS World News he believes seizing the phones of all detainees is "cruel" and "unnecessary."

“This is their connection with the world. It really is a life-saver for many people. Many people rely on their phone to communicate with their family, their loved ones, their lawyer, their advocates,” he said.

Border Force Commissioner Roman Quaedvlieg claimed earlier this year that phones were being used by asylum seekers to commit crimes.

However, Mr Newhouse believes the plan to seize phone is politically motivated.

“This is not only a means of criminalising those who seek asylum, but also to clamp down on information leaking from inside the government’s cruel and inhumane system,” he said.

“It will have impact of stifling freedom of information and freedom of speech, and the ability of those inside detention to communicate the horrors under which they are living.”

The ban would apply to ‘onshore’ detention centres, including Villawood and Christmas Island, not Nauru or Manus Island.